preamp/poweramp tubes in ole MARK IVA

[K-Roll]

hey guys,

i'm completely new to the forum, even though, I've been stalking around for quite some time now.
I've recently bought a mesa mark IV (US version, early A model) and it runs without any problems.

My only concern is the following -the sound is great, but I can definitely tell the tone lack definition when using my 7 string guitar when playing the low B string.. other than that, no general issues..


I've loaded it with new SED =C= 6L6 in the power amp stage, with bias set properly by a tech..

As for preamp tubes, i can tell there are: Groove tubes 12AX7 in V1 and V2, a Mesa 12 AX7A in V3, jan philipsECG ECC83 in V3 and something in those next two spots but cant remember clearly as i am at work.

my question is- can this muddiness be caused by preamp tubes? is there a way to decrease it?

My lead settings are: gain 8, bass 0, mid 8-9 trebles 9 fat and bright on, GEQ on with 750hz slightly cut out(but not extremely, i love to cut through) first two bass sliders boosted, trebles slighly above the middle line.. nothing extraordinary i'd say..
lead volume is somewhat around 5 i believe and the main output volume is just before 2.. simul class, pentode, harmonics..


i suppose it is not my guitar causing this as I have a quite high/mid trebbly custom sevenstring made of honduran mahogany, wenge top, rosewood plated ebony neck with ebony board - standard b tuning using 10-52s with a 63i believe for that low B noted mofo.. i had a plenty of 'healthy cut' when using the 5150 before

so, just checking with any of you who might have some ideas on how to tighten up without actually loosing that awesome growl and punch..
yeap and .. i'm running it straight into my EVH 5150 III cab.. witch matches just perfectly as it does not sound harsh, but smooth-ens up that bite.

thanks for any ideas, and if you've seen such questions many times before, shoot me dead bye

 

[dodger916]

Preamp tubes can definitely effect this. I would start by rolling that JAN/Philips into V1 and see what happens. Also see what's in V5 as that will effect global tone similar to V1 but not as extreme.

The =C=s are a good fit for the Mark IV.

 

[K-Roll]

thanks mate.. and sorry for such an extensive post, just wanted to make sure i reveal as much about my 'tone' as possible in order to get helped
i thought the jan philips is more of a low-gain preamp tube, but will definitely make sure to give it a try

i've also considered - dry filter caps - but.. as one has said before - something that is not broken does not need fixing, so at least for now, i think i'd like to avoid it as they seem to be (at least from a first glance) completely ok, no leaking, no spots

 

[swbo101]

To brighten it up try a Tung-Sol RI pre-amp tube just in the V1 position. I have a Mark IV A and I love that sound with that tube there.

edit: Forgot to add the RI

 

[dodger916]

To brighten it up try a Tung-Sol pre-amp tube just in the V1 position. I have a Mark IV A and I love that sound with that tube there.

I love Tung-Sols too in my Mark IVs, but I'm using vintage ones. I think these have great balance and introduce a desireable (for me) vintage vibe. I've found most vintage American tubes (RCA, Sylvania, GE, etc) to be balanced to bright. Amperex ECC83s (European) also tend to the bright side, but still balanced. I've found Mullards to be comparitively more mid to dark focused.

 

[K-Roll]

now i know exactly how i am running those..

V1- Groove tubes
V2- Groove tubes
V3- Mesa SPAX7-A
V4- Jan Philips
V5- Mesa SPAX7-A